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IsPosTo, IsToPos

Syntax

IsPosTo(R:RING):BOOL
IsToPos(R:RING):BOOL

where R is an identifier for a ring.
    

Summary

checks the module term-ordering of a ring

Description

The first function determines whether the ring R has the PosTo module term-ordering. The second function determines whether R has the ToPos module term-ordering. (These are the only possible module term-orderings in CoCoA.)

example

    
Use R ::= Q[x,y,z];
S ::= Q[x,y],PosTo;
IsPosTo(R);
FALSE
-------------------------------
IsToPos(R);
TRUE
-------------------------------
IsPosTo(S);
TRUE
-------------------------------
IsToPos(Var(RingEnv()));  -- to check the current ring, R
TRUE
-------------------------------